1. Field of the Invention
This invention relates to structure and processes for retaining electronic modules and components in physical and operative interrelationship to each other. More particularly, the present invention is concerned with apparatus and methods for stacking and interconnecting a multiplicity of electronic units in a mechanically and electrically interconnected relationship. Columnar racks of electronic equipment are established through use of the present invention.
2. Description of the Related Art
It is known in the art to form racks of modules of electronic equipment by creating an overall frame into which the modules are inserted. See for instance U.S. Pat. No. 5,291,838 by Ferchau et al and U.S. Pat. No. 5,298,681 by Swift et al. Electrical interconnections between the mounted modules are generally provided by a maze of external cabling, by cabling which passes through or along the tubular members forming the frame, or by special coupler adapters, such as those shown in U.S. Pat. No. 4,950,178 by Harvey et al and in U.S. Pat. No. 5,466,172 by Carstens et al.
The use of rack frames limits the number of modules or elements in a given stack, or else requires acceptance of greater space requirements if less than all the shelves of the frame are in use. Thus, others have endeavored to avoid use of discrete frames by adapting the elements for stacking by providing arrangements for retaining elements on top of each other. For example, U.S. Pat. No. 5,515,239 by Kamerman et al shows L-shaped shelf elements that are held in stacked relation between base and cap units by means of pivotal T-shaped connectors while cables electrically interconnect the elements through the use of D-type connectors. Another example of prior efforts to produce equipment racks by interlocking and stacking individual modules is suggested in U.S. Pat. No. 4,718,858 by Godfrey et al which employs a pivotal handle to both retain modules physically and to engage electrical connectors. U.S. Pat. No. 5,142,445 by Sorensen et al describes stackable modules that are held together by locking pins inserted into attachment feet channels beneath each module.
Despite the state of the prior art, the need persists for arrangements capable of securely retaining stacks of devices with a high degree of flexibility in accepting a relatively wide variety of module shapes and sizes in a rack-like configuration suitable for use or shipping as a unit while accommodating electrical communication and power interconnections between those modules.